Luke's expression hardened at that, a darkness stirring behind his blue eyes.

"I assure you, anyone on this train with the thought of harming someone just because they can would be dealt with. Quickly."

The temperature seemed to drop slightly at that, but it quickly returned to normal, almost like it had been caused by a fluctuation in the train's heating system, and not at all by Luke losing control of his anger for a brief moment. He let out a breath, shaking his head.

"In my galaxy, it's a little more common," he assured Bucky, pausing to roll up his sleeve so he could see where it connected to what remains of his real arm. "Especially among members of the military. My father has multiple prosthesis as well; this one is modeled after one of his."